Internal combustion engine



Feb. 13, 1934. NWEN 1,947,221

INTERNAL COMBUSTION ENGINE Original Filed March 23. 1928 IN VEN TOR.

,dem/z wan/014w ATTORNEY.

Patented Feb. 13, 1934 UNITED STATES PATENT OFFICE INTERNAL COMBUSTION ENGINE Original application March 23, 1928, Serial No.

264,265, now Patent No.

Divided and this applica- December 10, 1929.

1,739,255, dated tlon September 9, 1929. Serial No. 391,127

15 Claims.

My invention relates to air cooled internal combustlon engines and more particularly tosleeve valve and other similar types of engines, in which the cylinder is generally closed by a cylinder head having a portion depending within the cylinder and spaced therefrom to accommodate movement of one or more sleeve valves.

In air cooled engines of the above type. difficulty has been experienced in properly cooling that portion of the cylinder head depending within the cylinder. Various means have been suggested for deflecting the cooling air into the proper zone, but without great success, because the cooling air has not been confined to flow in a well defined path and as a consequence the cylinder head was rather inefliciently cooled resulting in an unsatisfactory performance of the engine.

It is the object of my invention to further improve the performance of an air cooled internal combustion engine of the above mentioned type by providing means for more efllciently cooling that portion of the cylinder head depending within the cylinder.

A further object of my invention is to provide more efficient cooling means for an engine of the above mentioned type by providing means for deflecting the cooling air in a well defined path,

into the reentrant portion of the cylinder head.

for obtaining a maximum cooling effect.

This application is a division of my copending application, Serial No. 264,265, filed March 23, 1928, that has matured into Patent No. 1,739,255, issued December 10, 1929.

For a more detailed understanding of my invention, reference may be had to the accompanying drawing which illustrates one form which my invention may assume, and in which:

Figure 1 is a sectional elevation view through a typical engine cylinder substantially along the line 1-1 of Fig. 3 and illustrating my invention,

Figure 2 is an elevational view of the upper portion of the cylinder and associated structure, and

Fig. 3 is a top plan view of the cylinder head assembly.

Referring to the drawing, reference character A represents a cylinder which in the sleeve valve air cooled type is provided with cooling fins 10, fuel intake 11 and exhaust 12. B is the cylinder head seated on the cylinder and secured thereto by fasteners 13, the head having a portion 14 depending wlthin the cylinder and spaced therefrom to provide a sleeve pocket 15. The cylinder head bottom 18 forms the top of the combustion chamber 17, one or more spark plugs 18 having terminals 19 communicating with the combustion chamber. Within the cylinder A is the usual reciprocating piston C and preferably intermediate the piston and cylinder are one or more sleeve valves, a single valve D of the combined reciprocating and oscillating type being shown for illustration. The sleeve D has the usual intake .and exhaust ports 20, 21 respectively cooperating with the cylinder intake and exhaust 11, 12 for producing the customary valving cycle.

In Figures 1 and 2 I have illustrated an improved means for dissipating the heat from the cylinder head. The head B is provided with substantially radial cooling fins 27 and 28 preferably extending from the lower wall 16 and depending portion 14 upwardly beyond the cylinder head proper. Preferably the fins 27 are of greater depth than the fins 28 for a purpose that will be more apparent hereafter. A current of cooling air indicated by arrows 29 approaches the upper ends of the fins 27, this air current being afforded by the slip stream when the engine is used for aircraft or by the well known-fan (not shown) or other induced draft means when the engine is usedfor stationary or general vehicular uses. In order to direct and confine the air current in the vicinity of the fins 27 for providing an improved cooling efficiency, I provide a defiector E having a portion 29 extending across the air stream 29 and extending downwardly into the cylinder head at the rear of fins 27. The deflector E also preferably has opposed side wings 30 confining the air stream at the sides of I and outwardly from the cylinder head.

It will be noted that the deflector E cooperates with the fins 2'7 in such a manner as to provide a plurality of open end air ducts for deflecting the cooling air in a plurality of well defined paths, conducting the said cooling medium from a zone substantially above the cylinder head to the lowermost portion of the reentrant cylinder head, thereby obtaining a more efllcient cooling of the engine which will result in an improved engine performance. The deflector, being associated with the fins of greater depth, provides air ducts of a size and capacity which will not restrict the air flow, and also fins of greater depth provide more cooling surfaces, which naturally dissipate a greater amount of heat than fins of a lesser cooling surface.

Although I have illustrated but one form of my invention and have described in detail but a single application thereof, it will be apparent to those skilled in the art to which my invention pertains that various modifications and changes may be made therein without departing from the spirit of my invention or from the scope of the appended claims.

What I claim as my invention is:

1. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder, a cooling fin within the recessed portion of the cylinder head, and an air deflector cooperating with said cooling fin and said cylinder head structure for deflecting the cooling air in a defined path bounded by the wall of said recessed portion and the inner edge of the fin into contact with the cooling fin.

2. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder, cooling fins within the recessed portion of the cylinder head, and an air deflector cooperating with said cooling fins for deflecting the cooling air in a defined path, intermediate of said fins and in contact therewith, said path bounded by the wall of said recessed portion and the inner edge of the fins.

3. In an air cooled combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder, cooling fins within the recessed portion of the cylinder-head, and an air deflector structure having a portion depending downwardly into the recessed portion to confine at least a portion of said cooling air to a defined path between two adjacent fins, said path bounded by the wall of said recessed portion and the inner edge of said fins.

4. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder, a cooling fin within the recessed portion of the cylinder head, and an air deflector contacting with said cooling fin and cooperating with the cylinder head structure for initially deflecting the cooling air in a defined path into contact with the cooling fin, said path bounded by the wall of said recessed portion and the inner edge of said fin.

5. In an air cooled combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder, cooling fins within the recessed portion of the cylinder head, and an air deflector structure having a portion depending downwardly into the recessed portion and cooperating with the fins to provide a plurality of ducts for said cooling air, said ducts bounded respectively by the wall of said recessed portion, said fins and the deflector.

6. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a

piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder, cooling fins within the recessed portion of the cylinder head, and an air deflector structure having a portion depending downwardly into the recessed portion of said cylinder head and cooperating with the flns to provide a plurality of closed air ducts for conducting the cooling air to the bottom of said recessed portion, said ducts separated by said fins and bounded by the wall of said recessed portion and the inner edge of said fins.

7. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, and a cylinder head structure having a recessed portion depending within the cylinder, a spark plug located in said recessed portion, said head provided with an open end closed duct for conducting the cooling air from a point substantially above the top of the cylinder head to a point adjacent the bottom of said recessed portion and below the outer extremity of said spark plug.

8. In an internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder, a cooling fin extending from the cylinder head substantially radially within the recessed portion thereof, an air deflector structure having a portion depending downwardly into the recessed portion adjacent the cooling fin, said defieetor structure having side wings adapted to confine cooling air adjacent the cooling fin.

9. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder and provided with cooling fins within the recessed portion of the cylinder head, said fins constructed of varying size, and means for deflecting cooling air in contact with said cooling fins.

10. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder and provided with cooling fins within the recessed portion of the cylinder head, some of said fins being of greater depth than the remaining fins, and an air deflector having a portion depending downwardly into the recessed portion of said cylinder head and cooperating with the fins of greater depth to provide one or more ducts for conducting the cooling air to the bottom of said recessed portion.

11. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder and provided with axially extending cooling fins within the recessed portion of the cylinder head, and an air deflector means cooperating with said fins for providing a plurality of separate air ducts, said deflector means acting to initially confine said air stream flow solely intermediate said fins.

12. In an air cooled internal combustion engine 01' the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder and provided with axially extending cooling fins within the recessed portion of the cylinder head, and an air deflector means cooperating with said fins for providing a plurality of separate air ducts for conducting said cooling air within said recessed portion.

13. In an air cooled internal combustion engine of the sleeve valve type, a cylinder structure, a piston, sleeve valve means, a cylinder head structure having a recessed portion depending within the cylinder and provided with axially extending cooling fins within the recessed portion or the cylinder head, and an air deflector means cooperating with said fins and contacting therewith for substantially its entire length to provide a plurality of separate air ducts within said recessed portion.

14. In an air cooled engine, a cylinder structure having a cylinder, a cylinder head structure closing one end of the cylinder, said cylinder head structure being positioned in the path of a stream of cooling air sweeping generally transversely across the top of said cylinder head, said cylinder head having a plurality of cooling fins projecting varying distances from the cylinder head to provide varying surface area to favor the dissipation or heat from one portion of the cylinder head more than from another portion, said cooling fins extending substantially in the direction of the cylinder axis.

15. In an air cooled engine, a cylinder structure having a cylinder, a cylinder head structure or the re-entrant type closing one end of the cylinder, said cylinderhead structure being positioned in the path of a stream of cooling air sweeping generally transversely across the top of said cylinder head, said cylinder head having one or more cooling fins extending generally parallel to the air stream, and a shell structure cooperating with said fin or fins and with said cylinder head to provide one or more ducts for directing said cooling air inwardly of said cylinder head.

ARCHIE MACPHAIL NIVEN. 

